+Perhaps the easiest way to work around quoting issues in a manner
+portable to all shells is to place the results in a temporary variable,
+then use @samp{$tmp} as the @var{value}, rather than trying to inline
+the expression needing quoting.

I wish you wouldn't use nor promote tmp as temporary variable name,
nor as a temporary macro name in tests/m4sh.at, given that it's already
documented as name of a temporary directory to use in config.status.